1. Field of the Invention
The present invention relates to a female plug coupling having three plug openings. More particularly, the present invention relates to an improved insert for a female plug coupling having three plug openings.
2. Description of the Related Art
Such plug couplings are in use in the USA and Japanese markets. For example, a plug coupling is shown in U.S. Pat. No. 5,647,751. According to the state of the art, female plug couplings consist of a two-part plastic material body in which the crimp connection pins for the conductor ends are inserted. The conductor ends are crimped on, i.e., fixed on, to the crimp connection pins and, the insert is extrusion-coated and thus forms the core of a grip body. The face side of this grip body has three plug openings arranged in a triangle to one another in a complementary manner to the contact pins of the connector plug. One of the connector plug contact pins is round, and the other two (current conducting) contact pins are rectangular.
In the manufacturing of the inserts for the plug coupling, problems have arisen in connection with the crimping-on of the conductor ends to the effect that it has proved difficult to perform the working step CRIMPING with a simple tool in a single operation. By reason of the arranging and assigning of the crimp connection ends in different topological planes, there is involved on the one hand a complicated tool and, on the other hand, different and in part diametrical force directions.
The present invention provides a plug coupling in which all the crimp connections lie in one and the same plane and which, therefore, can be executed in one operation with a simple one-piece tool.
In this regard, the special form of execution chosen for the crimp connection of the ground conductor has additionally proved to be especially advantageous, as the plugging force for the corresponding contact pin of the connector plug is relatively slight because of the shortness of the contact length of the plugging path. Both for the current conductor contact pins, and also for the protective conductor contact pin, there have been provided on the corresponding parts of the plug, coupling lugs or lashes which provide introduction aids.